The invention relates to an organic waste treatment system. More particularly, the invention relates to a system for treating pathogen containing organic waste, by which all pathogens are killed, and the waste is carbonized to produce a pathogen free acidic fertilizer.
Organic sludge, most commonly xe2x80x9csewerage sludgexe2x80x9d has traditionally created a disposal problem. However, in recent decades, attempts have been made to use the organic sludge as fertilizer. The main problem is using organic sludge is that it tends to contain pathogens which are harmful to humans and animals. Generally, the organic sludge is first processed through composting, such that heat generated during composting kills most parasites. However, composting is not fully effective in eliminating all harmful pathogens and parasites. In particular, the Ascaris Helminthes worm is a common parasite often found in organic sludge which can inhabit the intestines of humans and animals, but is generally not killed during composting.
Thus, when organic sludge is not completely sterilized, and is subsequently used as a fertilizer, significant danger exists. In particular, humans and domestic animals in farming communities are placed in direct jeopardy. Further, when organic sludge is used as a fertilizer there is a significant risk of contaminating the food chain and creating a wide reaching problem.
Although the Environmental Protection Agency has set criteria for the treatment, and subsequent reuse of organic sludge (see 40 CFR, parts 257 and 503), more stringent regulation is probably needed. However, in order to meet such prospective stringent regulations, a process must be developed which completely eliminates pathogens in organic sludge.
Other prior art attempts have been made to address the problem of pathogen reduction.
U.S. Pat. No. 6,312,492 to Wilson infuses animal manure with concentrated sulfuric acid and pine oil, dries the product, and uses it as a soil conditioner.
U.S. Pat. No. 5,422,015 employs an acid-base pair to disinfect pathogen containing organic sludge. The heat of hydration is used to attempt to pasteurize the organic sludge. However, this process does not teach the total destruction of the pathogen by carbonization. The process also increases the mass and volume of the organic sludge.
U.S. Pat. No. 5,378,257 to Higashida mixes nitric acid and quicklime with sewage to produce fertilizer.
U.S. Pat. No. 4,078,094 to Katzen uses an acid solution to react with a basic component in animal manure to form a soluble salt. The heat of hydration produced by the reaction is the basis for the attempted sterilization of the manure. U.S. Pat. No. 3,939,280 to Karnemaat uses acid, formaldehyde and urea to sterilize animal waste.
U.S. Pat. No. 4,369,199 to Katzen and U.S. Pat. No. 3,960,718 to Lebo both teach using acid to lower the pH of the organic material to 3 or 4 to destroy pathogenic bacteria and stop the production of unhealthy gases. However, neither process teaches the total destruction of pathogens by carbonization.
However, none of these systems ensure the total destruction of the pathogen, volume reduction of the organic sludge, the elimination of odors. Further, none have presented an economically viable solution.
Thus, while these units may be suitable for the particular purpose employed, or for general use, they would not be as suitable for the purposes of the present invention as disclosed hereafter.
It is an object of the invention to provide a system for processing organic sludge which completely eliminates pathogens within the sludge. Accordingly, the process fully carbonizes the organic sludge, as well as sterilizing and disinfecting the organic sludge, killing all living organic matter in the process.
It is another object of the invention to provide a system which produces acidic liquid fertilizer. Accordingly, the carbonization results in an effective, liquid fertilizer product, and the production of nitric and phosphoric acid increases the acidity of the fertilizer.
It is a further object of the invention to provide a system produces concentrated fertilizer whereby the mass and volume of the organic sludge is reduced so that the resulting fertilizer can be handled and transported more economically. Accordingly, the reaction of the present invention produces gases which are allowed to escape and result in a net reduction of mass and volume of the resultant liquid fertilizer.
The invention is an organic waste treatment process, for treating pathogen containing organic sludge and producing pathogen free liquid acidic fertilizer. Concentrated sulfuric acid is added to the organic sludge on a one-to-one basis with solids contained within the sludge. The concentrated sulfuric acid reacts with the organic sludge to neutralize pathogens by carbonizing the sludge, pasteurizing the sludge through heat of hydration, and chemically disinfecting the sludge through the production of sulfur dioxide. An efficient acidic liquid fertilizer is created by neutralizing the pathogens, by reacting with phospholipids and proteins to create phosphoric acid and nitric acid, and by a reduction in mass and volume through the production of waste gases that are allowed to escape.
To the accomplishment of the above and related objects the invention may be embodied in the form illustrated in the accompanying drawings. Attention is called to the fact, however, that the drawings are illustrative only. Variations are contemplated as being part of the invention, limited only by the scope of the claims.